The present invention relates to a developer conveying apparatus and an image forming apparatus.
A conventional image forming apparatus such as a printer, a copier, a facsimile machine, a complex machine is configured to form an image as follows. A surface of a photosensitive drum is uniformly charged by a charging roller. Then, the surface of the photosensitive drum is irradiated by an LED head so that a latent image is formed thereon. The latent image is developed by a developing roller in such a manner that a toner (i.e., a developer) forming a thin layer on the developing roller adheres to the latent image. The developed image (i.e., toner image) is transferred to a recording medium by a transfer roller. The residual toner remaining on the photosensitive drum after the transferring is scrapped off therefrom by a cleaning device, and is collected by the cleaning device.
The toner collected by the cleaning device is conveyed by a developer conveying apparatus to a developer storing container. The developer conveying apparatus has a conveying tube for conveying the toner. The conveying tube extends between the cleaning device and the developer storing container.
In some cases, detachable components of the image forming apparatus are disposed in the vicinity of the conveying tube. Therefore, the conveying tube is disposed so as to be curved, in order not to interfere with attachment/detachment of the detachable components (see, for example, Japanese Laid-open Patent Publication No. 8-314348).
A conveying spiral is provided inside the conveying tube. The conveying spiral is in the form of a coil, and is rotated to convey the developer through the conveying tube. The conveying spiral is curved along the curvature of the conveying tube.